I did this day as well in oforth, I was misusing tvars quite a bit I think, but the code would be so clunky without them.

Advent of Code--- Day 12: Leonardo's Monorail ---

You finally reach the top floor of this building: a garden with a slanted glass ceiling. Looks like there are no more stars to be had.

While sitting on a nearby bench amidst some tiger lilies, you manage to decrypt some of the files you extracted from the servers downstairs.

According to these documents, Easter Bunny HQ isn't just this building - it's a collection of buildings in the nearby area. They're all connected by a local monorail, and there's another building not far from here! Unfortunately, being night, the monorail is currently not operating.

You remotely connect to the monorail control systems and discover that the boot sequence expects a password. The password-checking logic (your puzzle input) is easy to extract, but the code it uses is strange: it's assembunny code designed for the new computer you just assembled. You'll have to execute the code and get the password.

The assembunny code you've extracted operates on four registers (a, b, c, and d) that start at 0 and can hold any integer. However, it seems to make use of only a few instructions:

cpy x y copies x (either an integer or the value of a register) into register y. inc x increases the value of register x by one. dec x decreases the value of register x by one. jnz x y jumps to an instruction y away (positive means forward; negative means backward), but only if x is not zero.

The jnz instruction moves relative to itself: an offset of -1 would continue at the previous instruction, while an offset of 2 would skip over the next instruction.

For example:

cpy 41 ainc ainc adec ajnz a 2dec a

The above code would set register a to 41, increase its value by 2, decrease its value by 1, and then skip the last dec a (because a is not zero, so the jnz a 2 skips it), leaving register a at 42. When you move past the last instruction, the program halts.

After executing the assembunny code in your puzzle input, what value is left in register a?

Your puzzle answer was 318083.--- Part Two ---

As you head down the fire escape to the monorail, you notice it didn't start; register c needs to be initialized to the position of the ignition key.

If you instead initialize register c to be 1, what value is now left in register a?

Your puzzle answer was 9227737.

Both parts of this puzzle are complete! They provide two gold stars: **

That's really cool, I was looking for something like #parse-name but I couldn't find it, I was trying to see how #tvar: and #import: was doing their magic, but they are probably using more internal code. I didn't get that.

That really lets you clean up the code a lot That's also a very neat trick with #register

Like always I'm amazed over how neat the code can be, and that is good, because it gives me something to aspire to

Also storing the program in a local variable in the run function also makes it neater, one less pesky tvar to worry about

The nice thing about a forth is that it's so malleable that one can do stuff in so many ways, there is almost always possible to find a very elegant way of solving some task I just have to pick up some more experience with it, so that I can pick up these more elegant ways.

For #import: , this is not buit-in. You can find its definition into the "Package.of" file.